The background description provided herein is for the purpose of generally presenting the context of the disclosure. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Mobile devices may use touch-screen actions to perform user interface functions and to improve and adapt the user experience. A potential downside to touch-screen interaction with applications that are highly visual is the touch controls consume portions of the screen. The act of touching the screen may result in blocking a portion of the screen from the user's view. This blocking may detract from the visual experience and decreases usability of the application, especially on small screen devices where screen real estate is limited. This problem may become more acute as augmented reality applications become more prevalent on mobile devices.
As an alternative to touch interfaces, active proximity, motion detection, and eye tracking systems can be used to detect user actions and perform functions based on these actions.
However high-fidelity detection systems with a nominal range in excess of 50 cm may be complex, expensive, and use an array of active sensors that take space and draw power. Therefore, such devices are not typically available on small portable devices.
The proximity sensors on the current crop of smart phones typically offer a nominal range of at most a few centimeters. Such range may have limited uses, such as to identify whether the phone is held close to the holder's ear, and may be inadequate to support complex user interface decisions when the device is held at an arm's length.
A large commercial game platform, such as the XBOX Kinect, is an example of a non-mobile computer-based system with active motion and proximity sensing. While highly accurate and capable of complex motion tracking, a large commercial game platform may not be very mobile and may be ill-suited for low power mobile use due to cost, size, and power draw.